Session:「Haptic Wearables」

論文アブストラクト：
A tactile display on the back of a smartwatch is an attractive output option; however, its channel capacity is limited owing to the small contact area. In order to expand the channel capacity, we considered using two perceptually distinct types of stimuli, wind and vibration, together on the same skin area. The result is a multimodal tactile display that combines wind and vibration to create "colored" tactile sensations on the wrist. As a first step toward this goal, we conducted in this study four user experiments with a wind-vibration tactile display to examine different ways of combining wind and vibration: Individual, Sequential, and Simultaneous. The results revealed the sequential combination of wind and vibration to exhibit the highest potential, with an information transfer capacity of 3.29 bits. In particular, the transition of tactile modality was perceived at an accuracy of 98.52%. The current results confirm the feasibility and potential of a multimodal tactile display combining wind and vibration.

Jetto: Using Lateral Force Feedback for Smartwatch Interactions

論文アブストラクト：
Interacting with media and games is a challenging user experience on smartwatches due to their small screens. We propose using lateral force feedback to enhance these experiences. When virtual objects on the smartwatch display visually collide or push the edge of the screen, we add haptic feedback so that the user also feels the impact. This addition creates the illusion of a virtual object that is physically hitting or pushing the smartwatch, from within the device itself. Using this approach, we extend virtual space and scenes into a 2D physical space. To create realistic lateral force feedback, we first examined the minimum change in force magnitude that is detectable by users in different directions and weight levels, finding an average JND of 49% across all tested conditions, with no significant effect of weight and force direction. We then developed a proof-of-concept hardware prototype called Jetto and demonstrated its unique capabilities through a set of impact-enhanced videos and games. Our preliminary user evaluations indicated the concept was welcomed and is regarded as a worthwhile addition to smartwatch output and media experiences.

HapCube: A Wearable Tactile Device to Provide Tangential and Normal Pseudo-Force Feedback on a Fingertip

論文アブストラクト：
Haptic devices allow a more immersive experience with Virtual and Augmented Reality. However, for a wider range of usage they need to be miniaturized while maintaining the quality of haptic feedback. In this study, we used two kinds of human sensory illusion of vibration. The first illusion involves creating a virtual force (pulling sensation) using asymmetric vibration, and the second involves imparting compliances of complex stress-strain curves (i.e. force-displacement curves of mechanical keyboards) to a rigid object by changing the frequency and amplitude of vibration. Using these two illusions, we developed a wearable tactile device named HapCube, consisting of three orthogonal voicecoil actuators. Four measurement tests and four user tests confirmed that 1) a combination of two orthogonal asymmetric vibrations could provide a 2D virtual force in any tangential directions on a finger pad, and 2) a single voicecoil actuator produced pseudo-force feedback of the complex compliance curves in the normal direction.

PokeRing: Notifications by Poking Around the Finger

論文アブストラクト：
Smart-rings are ideal for subtle and always-available haptic notifications due to their direct contact with the skin. Previous researchers have highlighted the feasibility of haptic technology in smart-rings and their promise in delivering noticeable stimulations by poking a limited set of planar locations on the finger. However, the full potential of poking as a mechanism to deliver richer and more expressive information on the finger is overlooked. With three studies and a total of 76 participants, we informed the design of PokeRing, a smart-ring capable of delivering information via stimulating eight different locations around the index finger's proximal phalanx. We report our evaluation of the performance of PokeRing in semi-realistic wearable conditions, (standing and walking), and its effective usage for information transfer with twenty-one spatio-temporal patterns designed by six interaction designers in a workshop. Finally, we present three applications that exploit PokeRing's notification usages.